LONDON – The reckoning has already begun for outgoing Chancellor Angela Merkel’s conservative alliance, a day after election results pointed to its worst ever showing since its formation at the end of World War II.

Pressure is mounting within the Christian Democratic Union-Christian Social Union bloc after preliminary results published Monday showed that the center-right alliance achieved 24.1% of the vote, compared to 25.7% for the center-left Social Democratic Party.

The results make a coalition government necessary and it’s looking increasingly likely that the CDU-CSU may be heading into opposition although its candidate for chancellor, Armin Laschet, has still insisted that the bloc has a mandate to govern.

Having essentially ruled out forming another so-called “grand coalition” together, both the SPD and CDU-CSU are now preparing to court two smaller parties — the Greens and the pro-business Free Democrats — with the aim of enticing them into a governing alliance.

For their part, the Greens and FDP who are now effectively in the position of kingmakers, look set to discuss their respective positions together this week before engaging with the larger parties.

Despite acknowledging that his party had fallen short of expectations, Laschet said Monday that he was optimistic about forming a coalition.

“There is no question that this result cannot, must not and will not satisfy the Union. We managed to catch up in the final spurt and prevented red-red-green, but at the same time there are painful losses. It was not enough for first place,” he told party members.

Despite Laschet’s optimism, the soul-searching has already begun in Merkel’s CDU party with a clamor growing for Laschet to resign, German media widely reported Tuesday morning.

Criticism of Laschet had grown overnight, the Bild newspaper reported Tuesday, with leading CDU officials saying that the party should accept the will of the voters and concede victory to the SPD. There are rumblings in the German media that pressure could be exerted on Laschet to stand down.

The newspaper quoted Lower Saxony’s CDU boss Bernd Althusmann as commenting that “we should now humbly and respectfully accept the will of the voters, with decency and attitude. Change was wanted.”

Meanwhile, Hesse’s Prime Minister Volker Bouffier noted that the CDU-CSU has “no claim to government responsibility” while Tilman Kuban, the head of Junge Union (the young wing of the CDU-CSU) was quoted as saying “we lost the election. Period. The clear mandate lies with the SPD, Greens and FDP.”

Adding insult to injury, the Bild newspaper reported a survey by polling institute Forsa on Tuesday suggesting that the CDU-CSU union could have achieved 30% of the vote if Markus Söder (the head of the CSU) had been the bloc’s candidate for chancellor instead of Laschet.

The electorate seems to agree that Laschet should not claim a mandate to govern, with most Germans opposing the prospect of another conservative-led government.

According to an opinion poll by the Civey institute for the Augsburger Allgemeine daily, 71% of over 5,000 respondents oppose Laschet trying to become chancellor after the party’s poor performance. The poll, conducted Sunday and Monday, found that only 22% of Germans supported Laschet’s claim to have a mandate to form a government.

A bad trend
The latest blow for the CDU cannot all be blamed on Laschet, seen as a successor to Merkel but far from as well-liked as his predecessor, as the decline in the CDU’s share of the vote continues a trend seen in the last couple of elections.

Still, it comes at a time of vulnerability for the conservatives ahead of the departure of Merkel who has led Germany for 16 years.

In the election on Sunday, and without the CSU (its Bavarian sister party) the CDU achieved just 18.9% of the vote, down 7.9 percentage points from the 2017 vote. Conversely, the SPD has seen its share of the vote rise 5.2 percentage points since 2017, as did the Greens and Free Democrats, official data from the Federal Returning Officer show.

Jeffrey Rathke, president of the American Institute for Contemporary German Studies, Tuesday that while it was important not to write Laschet off just yet “all the bets now are on the Greens and the FDP trying to find a way to work with Olaf Scholz and the Social Democrats.”

Marco Willner, head of Investment Strategy of NN Investment Partners, was keen to emphasize that coalition talks could take some time.

“It’s a very strange situation at the moment where really, for the first time, the small, junior partners in this coalition set the tone and are looking to choose the senior partner in this game. Clearly the SPD have the lead here but it’s day two after the elections and I expect this to go on for some time and who knows down the road where this will lead to,” he told CNBC’s “Squawk Box Europe” Tuesday.

Why did the CDU do so badly?
There are several reasons why Merkel’s party is judged to have fared badly in this latest election, including the rise of a younger, more environmentally-conscious electorate to an increasing number of voters who want to see Germany invest in itself and modernize its infrastructure, be it in the industrial, digital or transport sectors.

“What’s required economically [in Germany] is significant change,” Clemens Fuest, president of Germany’s respected Ifo Institute, told CNBC Tuesday. “We are facing challenges like climate change and digitization so the challenge will be to have a three-party coalition that has to compromise a lot,” he noted.

FDP and Greens are in the driver’s seat, Germany’s Wieland says
Another of the reasons the party has fared worse in this vote is undoubtedly due to the imminent departure of Merkel. Experts note that previous votes for the CDU-CSU bloc were in fact votes for Merkel, a trusted leader who attracted voters for her pragmatic and steady approach to politics both at home and abroad.

Despite attempts to make Laschet appeal to voters as a continuity candidate and someone who can fill Merkel’s shoes, he has not had the same appeal, and has even managed to alienate many during the election campaign, having been caught on camera laughing during a visit to a flood-hit German town.

For some, Laschet’s biggest disadvantage was that he simply wasn’t as likeable a candidate as his main rival Olaf Scholz, and that he just simply isn’t Merkel.

Matthew Oxenford, Europe analyst at the Economist Intelligence Unit, noted simply that “Scholz proved a much more compelling chancellor candidate than the CDU/CSU’s Armin Laschet” while Thomas Gschwend, a professor at the Department of Political Science at the University of Mannheim, told CNBC ahead of the vote that “the CDU tried to stage their campaign that Laschet was a natural successor of Merkel, but people just didn’t buy this story because he’s not Merkel, he’s not like her.”